export default {
	namespaced: true,
	
	state: () => ({
		//购物车的数组，用来存储购物车每个商品的信息对象
		//每个商品的信息对象，都包含如下6个属性：
		//{ goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
		cart: JSON.parse(uni.getStorageSync('cart') || '[]')
	}),
	
	mutations: {
		addToCart(state,goods){
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
			
			if(!findResult){
				state.cart.push(goods)
			} else {
				findResult.goods_count++
			}
			this.commit('m_cart/saveToStorage')
		},
		saveToStorage(state){
			uni.setStorageSync('cart',JSON.stringify(state.cart))
		},
		//更新购物车中商品的勾选状态
		updateGoodsState(state,goods) {
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
			
			if(findResult) {
				findResult.goods_state = goods.goods_state
				
				this.commit('m_cart/saveToStorage')
			}
		},
		//更新商品的数量
		updateGoodsCount(state,goods){
			const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
		
			if(findResult) {
				findResult.goods_count = goods.goods_count
				
				this.commit('m_cart/saveToStorage')
			}
		},
		//根据Id删除对应的商品
		removeGoodsById(state,goods_id){
			state.cart = state.cart.filter(x => x.goods_id !== goods_id)
			
			this.commit('m_cart/saveToStorage')
		},
		//更新购物车中所有商品的勾选状态
		updateAllGoodsState(state,newState){
			state.cart.forEach(x => x.goods_state = newState)
			
			this.commit('m_cart/saveToStorage')
		}
	},
	
	getters: {
		//购物车中所以商品的总数量
		total(state){
			// let c = 0
			// state.cart.forEach(x => c += x.goods_count)
			// return c
			
			return state.cart.reduce((total,item) => total += item.goods_count , 0)
		},
		//购物车中已勾选商品的总数量
		checkedCount(state){
			return state.cart.filter(x => x.goods_state).reduce((total , item) => total += item.goods_count , 0)
		},
		//已勾选商品的总价格
		checkedGoodsAmount(state){
			return state.cart.filter(x => x.goods_state).reduce((total,item) => total += item.goods_count * item.goods_price , 0).toFixed(2)
		}
	}
}